The present invention relates to a method of arranging colors to figures displayed on a display screen.
In a conventional display apparatus, when colors are arranged to a figure constructed by a plurality of areas, it is necessary to designate desired colors to the areas one by one.
For example, a case of arranging colors to a stack bar graph as shown in FIG. 1 is considered. It is assumed that red is designated to three areas 111, 112, and 113, blue is designated to three areas 121, 122, and 123, and green is designated to three areas 131, 132, and 133.
According to a conventional method, colors are arranged by designating and painting colors to the total nine areas one by one in a manner such that red is designated and painted to the area 111, red is similarly designated and painted to the area 112, red is similarly designated and painted to the area 113, blue is designated and painted to the area 121, and the like.
The number of color designations can be reduced by linking the areas to be painted the same color and regarding the linked areas as one area. Referring to FIG. 1, the three areas 111, 112, and 113 are regarded as one area and red is designated to the area, thereby enabling the three areas to be colored in a lump. By combining the areas as mentioned above, all of the nine areas can be colored by total three operations in the example of FIG. 1.
In such a conventional method, however, the color designating operations have to be still performed by the number corresponding to the number of areas to be colored.
There are cases of using colors just to make areas distinguished irrespective of color itself. For example, a graph formation is a typical example of such a case and a main purpose of arranging colors is to just distinguish elements by using colors. Particularly, when the number of component elements is large, the number of color designations is accordingly large, so that there is a problem such that it is troublesome to operate.
There is a method of arranging colors which intends to obtain a visual effect by regular variations in hue, for example, a case of expressing a gradation in the areas.
The gradation expression is such that density and lightness of color, ratio of color in a predetermined area, and the like are adjusted with certain regularity to gradually arrange colors, thereby obtaining the visual effect by the lightness/darkness of color and hue variations.
For example, the areas 131, 132, and 133 in FIG. 1 are set to red, the areas 121, 122, and 123 are set to red of which density is half of the color in the areas 131, 132, and 133 (it shows a state such that the half of the number of dots per unit area is red dots and the other half is white dots) and the areas 111, 112, and 113 are set to red of which density is the half of the color in the areas 121, 122, and 123.
Even in such a case, according to the conventional method, it is necessary to designate colors by the number of areas in consideration of the regularity.